Re: [RFC/PATCH 0/4] CPUSET driven CPU isolation

Paul Jackson
2008-02-29T03:34:21Z

David, responding to pj, responding to ...:
>
> > > Move the watchdog/0 thread to a cpuset that doesn't have access to cpu 0.
> >
> > I still don't understand ... you must have some context in mind that
> > I've spaced out ... I can't even tell if that is a statement or a
> > question.
> >
>
> You said that you weren't aware of any problems that could arise that are
> fixed with this added check in set_cpus_allowed(),

Ok, now I understand your question - thanks.

I think your question arises from misreading what I wrote.

I did not say that I wasn't "aware of any problems that could arise"

I did say, as you quoted, from Thu, 28 Feb 2008 11:37:28 -0600:
>
> I don't have strong opinions either way on this patch; it adds an error
> check that makes sense. I haven't seen much problem not having this check,
> nor do I know of any code that depends on doing what this check prohibits.

- This does not say no (none whatsoever) problem could (ever in the future) arise.

- This does say not much (just a little) problem had arisen (so far in the past).

Apparently, you thought I was trying to reject the patch on the grounds
that no such problem could ever occur, and you were showing how such a
problem could occur. I wasn't trying to reject the patch, and I agree
that the check made sense, and I agree that such a problem could occur,
as your example shows.

--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <pj@sgi.com> 1.940.382.4214